They can literally stop the network though by perpetrating their own attacks. Even if the bitcoin network is perfectly secure to a subtle cyber attack in the ve

They can literally stop the network though by perpetrating their own attacks. Even if the bitcoin network is perfectly secure to a subtle cyber attack in the vein of stuxnet, all the US or any major power would need to do is bring the mining power low enough that it can undermine the block chain through brute force. Honestly seems more likely to be a tactic employed in China though due to the more top down nature of that country's power structure.